Hey there, I've got a list of lists with matrices: A list with 13 entries (representing years), each of them another list with 12 matrices (representing one month). In each matrix there are as many rows as there are hours in the different months and 2 columns, since two meteorological parameters are measured. What I want to do is to calculate the hourly mean values for each month over the whole 13 year period
for (j in 1:12){ (list[[1]][[j]] [1,1] + list[[2]][[j]] [1,1] + ...... list[[13]][[j]][1,1] )/13 } How can I do that nicely? Original code looks like this (zeilen[j] is the number of hours for j=1 = January, 2 = february and so on): mean_list<-list() for (j in 1:12){ mean_list[[j]]<-matrix(0,nrow=zeilen[j], ncol=2) for (k in 1:zeilen[j]){ mean_list[[j]][k,1]<- (biglist_new[[1]][[j]][k,1]+biglist_new[[2]][[j]][k,1]+biglist_new[[3]][[j]][k,1]+biglist_new[[4]][[j]][k,1]+biglist_new[[5]][[j]][k,1]+biglist_new[[6]][[j]][k,1]+biglist_new[[7]][[j]][k,1]+biglist_new[[8]][[j]][k,1]+biglist_new[[9]][[j]][k,1]+biglist_new[[10]][[j]][k,1]+biglist_new[[11]][[j]][k,1]+biglist_new[[12]][[j]][k,1]+biglist_new[[13]][[j]][k,1])/13 mean_list[[j]][k,2]<- (biglist_new[[1]][[j]][k,2]+biglist_new[[2]][[j]][k,2]+biglist_new[[3]][[j]][k,2]+biglist_new[[4]][[j]][k,2]+biglist_new[[5]][[j]][k,2]+biglist_new[[6]][[j]][k,2]+biglist_new[[7]][[j]][k,2]+biglist_new[[8]][[j]][k,2]+biglist_new[[9]][[j]][k,2]+biglist_new[[10]][[j]][k,2]+biglist_new[[11]][[j]][k,2]+biglist_new[[12]][[j]][k,2]+biglist_new[[13]][[j]][k,2])/13 } } -- View this message in context: http://r.789695.n4.nabble.com/Mean-of-matrices-entries-in-list-of-lists-tp4649054.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.